Stent and medical device comprising same

Abstract

A stent 51 c is formed by braiding a plurality of filament threads containing a biodegradable polymer into a cylindrical braid, and connecting points 53 a - 53 d at end portions of the filament threads constituting the braid are arranged in two or more rows in a length direction of the braid. Elastic threads 54 a - 54 d are each disposed outside at least a part of the stent 51 c and along at least a part of the stent in the length direction including the vicinity of either one of end portions of the stent. One end of each elastic thread is fixed to the vicinity of the end portion of the stent, and the other end is fixed to any portion of the stent. In a state in which the stent is radially contracted, tension may be applied to the elastic threads. Thus, provided are a stent that is easy to load into a delivery system and also facilitates the expanding operation, as well as a medical device including the stent.

1 . A stent which is formed by braiding a plurality of filament threads containing a biodegradable polymer into a cylindrical braid,
 wherein connecting points at end portions of the filament threads constituting the braid are arranged in two or more rows in a length direction of the braid, and   a plurality of elastic threads are further incorporated in the braid as warp threads and extend in the length direction, with both ends of the elastic threads being fixed to the braid.   
     
     
         2 . The stent according to  claim 1 , wherein the connecting points are formed using at least one connecting method selected from thermal fusion bonding, ultrasonic fusion bonding, and joining with the use of one of an adhesive, a metal tube, and a resin tube. 
     
     
         3 . The stent according to  claim 1 , wherein each of the filament threads constituting the braid is a monofilament thread. 
     
     
         4 . The stent according to  claim 1 , wherein the braid is constituted by 16 or more filament threads. 
     
     
         5 . (canceled) 
     
     
         6 . The stent according to  claim 1 , wherein the elastic threads are disposed outside at least a part of the stent and along at least a part of the stent in the length direction including the vicinity of either one of end portions of the stent,
 an end of the elastic thread is fixed to the vicinity of the end portion of the stent, and another end of the elastic thread is fixed to any portion of the stent, and   in a state in which the stent is radially contracted, tension is applied to the elastic threads.   
     
     
         7 . The stent according to  claim 1 , wherein the elastic threads are threads made of at least one selected from polyurethane, a rubber, and a thermoplastic elastomer that are biocompatible. 
     
     
         8 . The stent according to  claim 1 , wherein each of the elastic threads is fixed to or crosses a constituent thread of the braid to form a fixing point or a contact point at a position that is closer to the middle than an end portion of the stent. 
     
     
         9 . The stent according to  claim 8 , wherein the fixing point or the contact point where the elastic thread is fixed to or crosses the constituent thread of the stent is located at a distance of ⅛ to ½ of a stent length from the end portion of the stent. 
     
     
         10 . The stent according to  claim 1 , wherein tension applied to the elastic threads in a state in which the stent is radially contracted is 0.1 to 5.0 N/thread. 
     
     
         11 . The stent according to  claim 1 , wherein three to six of said elastic threads are arranged at regular intervals in a circumferential direction when viewed in a cross section of the stent. 
     
     
         12 . The stent according to  claim 1 , wherein the elastic threads are fixed to the stent through joining using at least one selected from thermal fusion bonding, ultrasonic fusion bonding, an adhesive, a metal fixing member, and a resin fixing member, or tying of the elastic threads to constituent filament threads of the stent. 
     
     
         13 . The stent according to  claim 1 , wherein the stent is a gastrointestinal stent. 
     
     
         14 . A medical device comprising a stent which is formed by braiding a plurality of filament threads containing a biodegradable polymer into a cylindrical braid,
 wherein in the stent, connecting points at end portions of the filament threads constituting the braid are arranged in two or more rows in a length direction of the braid, and   a plurality of elastic threads are further incorporated in the braid as warp threads and extend in the length direction, with both ends of the elastic threads being fixed to the braid.   
     
     
         15 - 16 . (canceled) 
     
     
         17 . The medical device according to  claim 14 , wherein the medical device is for treatment of a gastrointestinal stenosis. 
     
     
         18 . The medical device according to  claim 14 , further comprising a delivery system. 
     
     
         19 . The-medical device according to  claim 18 ,
 wherein the stent loaded into the delivery system,
 the stent is formed by braiding the filament threads containing the biodegradable polymer into the cylindrical braid, 
 in the stent, the connecting points at the end portions of the filament threads constituting the braid are arranged in two or more rows in the length direction of the braid, and 
   the elastic threads are further incorporated in the braid as the warp threads and extend in the length direction, with the both ends of the elastic threads being fixed to the braid.